(5+а)(5-а)=?, (m+n)(m+n)=?, (2-b)(2-b)=?, (2a-b)(b+2a)=?, (2a+b)(b-2a)=?

Question

(5+а)(5-а)=?, (m+n)(m+n)=?, (2-b)(2-b)=?, (2a-b)(b+2a)=?, (2a+b)(b-2a)=?

Answer 1

Вот решение............

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Answer 2

(5+а)(5-а)=5²-а²=25-а²,
(m+n)(m+n)=(m+n)²=m²+2nm+n²
(2-b)(2-b)=(2-b)²=4-4b+b²
(2a-b)(b+2a)=(2a)²-b²=4a²-b²
(2a+b)(b-2a)= b²-(2a)²= b²-4a²